Truffles: Gold in the Soil

Truffles
have fascinated people for thousands of years. Their attraction is a
tantalizing taste and aroma which, once experienced, can never be forgotten.
The taste and aroma of commercially collected truffles is so intense that they
are used as a flavoring instead of a separate dish. Magical powers and virtues
have even been attributed to truffles. They have been collected for at least
3600 years. Growing underground, they are difficult to find and very
expensive as a result. Every Spring, truffle hunters in Europe take to the
woods, hoping that the sensitive noses of their trained pigs and dogs will lead
them to buried treasure. In November, 2000, a new record of over $400 an
ounce was set an an auction of white truffles. At those prices, the average
two-ounce candy bar would cost you $800!

The name truffle has been borrowed to describe small, fancy
chocolate candies, another expensive and delicious food. Real truffles are
roundish, brown, and dirty when they come out of the ground. They are the fruit
of the truffle organism, like apples are the fruit of an apple tree. Truffles
contain spores for reproduction the way an apple
contains apple seeds.

Many animals can easily reach fallen apples, and so spread their seeds by way
of uneaten cores, or in dung. Since truffles are buried in the soil, truffles
rely on partnerships (symbiosis) with certain animals for spore dispersal.
Squirrels and chipmunks dig up truffles in the same way they may steal flower
bulbs in your garden. They are the major wild animals dispersing truffle spores
in North America.

Truffle-producing fungi have also formed symbioses with trees (mycorrhizae) because fungi cannot make their own food.
The hyphae, or thread-like non- fruiting part of these fungi, coat the roots of
the tree and help their host absorb soil minerals. In return, the tree host
provides the fungus with carbohydrates and other nutrients, the product of the
trees photosynthesis.

Attempts are being made to farm truffles due to the difficulty in finding them
in the wild. The harvest has steadily decreased for the last 90 years, due to
forest destruction and the killing of trees by air pollution. France produced
1,000 metric tonnes of truffles in 1892; now, only 50-90 tonnes are harvested
each year.